Porous polyethylene (pPE) implants are well established medical products which have been in use for many years. The materials are biocompatible and are well accepted by the medical community. However, cell growth into these conventional pPE scaffolds is poor. Surface modification to the polymer has been tried to improve cell growth. Such approaches include surface modification by self assembled monolayer formation, functionalization through silane molecules, layer-by-layer assembly, nano-indentation and etching with various advantages and disadvantages.
Gugala et al in J. Biomed Mater Res A, 2006, 76, 288 uses various plasma to study the attachment characteristics of osteoblasts on nonporous and porous polylactide. They conclude that ammonia treatment resulted in highest number of attached cells, but a longer duration of this treatment may prove detrimental to the polymer and is therefore avoided.
U.S. Pat. No. 5,387,237 relates to a bioartificial implantable pancreas for the treatment of insulin dependent diabetes mellitus. The bioartificial organ for implantation comprises a biocompatible fibrous or foam matrix in the vascularizing chamber. The matrix material is composed of organic or inorganic material, the organic material selected from polyolefins such as polyethylene, polypropylene etc. which are non halogenated and non fluorinated. The matrix thickness thus allows sufficient absorption of proteins, ECM materials, growth factor materials, develop blood supply, and the matrix also is preferably non-absorbable by the body of the mammal and minimizes fibriotic overgrowth and encapsulation.
U.S. Pat. No. 6,551,608 relates to novel porous materials that possess antiviral and/or antimicrobial properties. The invention encompasses a porous material having antiviral or antimicrobial properties which is comprised of a porous substrate and an antiviral or antimicrobial agent to overcome the need for porous, non-fibrous materials that resist the accumulation or growth of viruses and/or microbes. The process of preparation of the novel particles comprises sintering of tie thermoplastic material with the antimicrobial agent.
Thus the prior art review clearly brings out a need in the art for compositions of polymer with enhanced cell growth properties. Further there is a need in the art to provide processes for preparing such compositions and identify the various Cells that can grow on such membranes.
Literature reports indicate that transition metals in ionic or metallic form posses antimicrobial action, exemplified herein in Ag ions, but are unstable, particularly in aqueous medium and cannot exert their antimicrobial action for a sustained period of time. In the instant invention, the objective is to provide a composition of a polymer that serves as a reservoir, it is necessary that there is a sustained action of an anti microbial agent to prevent formation of bio film. To overcome these drawbacks, the inventors propose a simple process of reducing Ag ions to nanoparticles and capping them using the same agent, thereby accomplishing the objective of providing sustained anti-microbial action and the polymer-anti microbial composition retaining it functionality as desired since the Ag nanoparticles are preventing formation of bio film.